The Ruined Death Knight - Chapter 371: Hollow Bodyguards of Two

Ling Xiao was a powerful martial expert who fell in battle and was unexpectedly transmigrated into another world. He began life anew in the body of a boy with the same name, a fallen genius of the Ling Family whose cultivation had been crippled in a surprise attack, and son to a father who had also suspiciously been crippled under similar circumstances. Armed with knowledge from his previous life, Ling Xiao aim to restore his strength and establish his place at the top of this new world

- Description from Novelupdates

The young lord of a small and weak country saves a dragon beside the sea one day.

The mysterious master returned to the village, skilled in medicine and Martial Arts, using extraordinary methods to lead the villagers on a path to wealth.

Zhang Gong decides to learn light magic, a magic few show interest in and eventually becomes the legendary Grand Magister. While trying to end the continent’s east and west separation in order to unite all of the different races, he becomes every race’s Child of Light.